During the last few years, bottom mount refrigerators, with drawers in their bottom part, have been re-introduced in the market. A refrigerator with a drawer in its lower part has the fresh food compartment placed vertically in the upper part of a drawer or freezing compartment. The freezing compartment is usually smaller than the fresh food compartment.
There are different types of mounting mechanisms to close the front access of the lower drawer. In one embodiment, the freezer door is mounted with hinges to the refrigerator compartment cabinet, to allow the door to rotate in a vertical axis to open. In another embodiment, the door rolls or rotates in a horizontal axis.
In yet another embodiment of lower drawer mounting, said drawer slides moving horizontally relative to the refrigerator compartment. In this embodiment, the door inner cover or liner is fixed with rails that extend telescopically from the freezer compartment to allow the front door to slide in a horizontal axis relative to said compartment, to carry out the respective aperture and closure of the freezer compartment. Typically, this sliding compartment has a drawer or container, in which food articles are stored, and are accessible to the user when the door slides to open the compartment. In general, the articles that are stored in the drawer or container within the compartment, are articles with a given weight, and they tend to gain weight when frozen. Therefore a mechanism capable of supporting a substantial weight is needed, as well as a reliable, economic and easy to mount is needed.
In the art, the drawers had rails that did not correctly distribute the weight of the drawer, and were directly mounted to the compartment liner walls. An example of this, is U.S. Pat. No. 4,936,641, which discloses mounting system for an article supporting member in a refrigerator includes first and second support members, each one is secured and mounted to the compartment liner lateral walls so that the height member of the support members may be adjusted. In another patent which discloses similar rails, that are not telescopic, is U.S. Pat. No. 5,980,009, wherein the rails uses ball bearings to slide the drawer by means of beams. Another patent that discloses this type of rails, is U.S. Pat. No. 4,788,832, wherein the rail support is directly attached to the freezer compartment liner.
Telescopic rails in refrigerators were disclosed in U.S. Pat. No. 2,103,885, which discloses a refrigerator capable of increasing wasted space for increasing refrigerator capacity. Another telescopic rail disclosed in the art, is that of U.S. Pat. No. 2,711,944. In said patent, the telescopic rails are supported by a pair of angled brackets, at the same time, the supports are directly fixed to the liner.
There are several patents that disclose in the art rails or telescopic rails, as well as rail supports to mount drawers with substantial weight. For example, U.S. Pat. No. 6,971,730, discloses a freezer drawer, specifically a mechanism to mount drawers to a refrigerator compartment. The drawer uses a pair of lateral adapters having a front section and a respective canal. Rails for the drawer, which are telescopic, are mounted to the canal of the first and second lateral adapters, with the disadvantage that these rails are loose within the canal. As seen in FIG. 5, an upper lug shown with numeral 127, lies over the upper groove of the liner, shown with numeral 66. On the other hand, a lower lug shown with numeral 147, lines over the lower groove of the liner, shown with numeral 67. This effect of resting the rail support over the liner, creates friction between the parts, that will eventually lead to the deterioration of the pieces, being a non-desired problem. Having the lugs in the rail support and grooves in the liner, makes the assembly of the parts a complicated and costly process. Additionally, the mold to make the rail support, with said grooves, is difficult to achieve and produce, being that the tolerances of the process are minimum in view of the grooves and lugs, since the product has to be cooled for assembly, otherwise, it is possible that the product may fracture or even break. Having lugs in the rail support, gives the rail support little adaptability to different compartment models, for example, the rail support may not be coupled to flat walls, unless the wall has grooves as those disclosed by said patent. Additionally, having said grooves also renders a rail support which is inadaptable to different freezer models. Having lugs in the rail support that lies over the compartment liner wall grooves, creates the disadvantage that when the drawer slides in a horizontal axis, the rail support moves, and therefore, the whole drawer may be extracted in an unaware manner, further to creating instability in view of the drawer's weight. The quantity of material used to achieve the rail support in said patent, is excessive, in view of the wasted material parts, as is found in the upper wall, shown with numeral 97. Being that the used material quantity by said patent is greater, the final product is heaver, thus, having as a repercussion the deterioration of the wall. The section for fixing the drawer to the rails while sliding in a horizontal axis towards the outer part with regards to the upper compartment, shown with numeral 188, which is observed in FIG. 2 of said patent, does not totally stop the drawer, that is, if the mechanism is oppressed towards the inner part, the drawer may be easily loosened. The US patent does not disclose or suggest the use of a rack and pinion separate to the rail, as does the present invention so that the rails may synchronically slide the same length. This patent, has as part of its family, U.S. Pat. No. 7,240,980 and U.S. patent application Ser. No. 11/758,169, with publication No. 2007/0227180.
None of the prior art documents disclose a rail mechanism and a rail support mechanism that is easy to assemble and that may be adapted to any type of wall. Furthermore, none of the prior art documents disclose a slide mechanism and a drawer support mechanism that is easy to produce.
Therefore, the above mentioned problematic exists in the prior art. An additional problem is that a rail and a rail support mechanism that are easy to assemble and produce, which at the same time have a high adaptability to different types of walls is not disclosed. Likewise, there are not rail supporting or fastening mechanisms that are capable of sustaining a substantial weight, without resting over the wall grooves. In view of the above, there are not rail supporting or fastening mechanisms that do not deteriorate the wall on which it rests, and as a consequence, its life expectancy is diminished. The rails and rail support mechanisms that are capable of sustaining substantial weight and not deteriorating the walls, require a great quantity of materials to be made.
A further problem is that the drawers may be unexpectedly removed by a user. Yet another problem found in the telescopic rails of the art, is that when opening or closing the drawer, i.e. when sliding the drawer in a horizontal axis, the lateral ends of the drawer tend to misalign creating a non-uniform sealing of the drawer door with regards to the compartment.